Thank you for your patience, gazumped ?.
I get the public link from Evernote Desktop using the 'Compartir\Copiar enlace para compartir' menu option (look at the attached image). In english the menu option may be 'Share \ Copy link to share'. Then I paste the link into another note in the same database. This hyperlink doesn't works in my Android. I want the note opens in Android app, although it would be enough that the note opens in a web browser. Nothing happens except the error message "please make sure your account is synchronized and that the note has not been deleted. If you are the owner of the note, you must have logged in to the account associated with this note"
One mistery.